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Originally Posted by Keith Atlanta
(Post 4851049)
Are those intake plenums bigger than the stock 8.1/496? They look a little bigger... The throat is 4 bolt rather than 3 as well, the TB hole looks bigger as well.
Looking through the TB mount into the plenum, it looks massive inside. Pics do not convey this very well. |
Originally Posted by Dragracer_Art
(Post 4851051)
Looking through the TB mount into the plenum, it looks massive inside. Pics do not convey this very well.
The stock aperture may have only been 90, might have even been 85 |
Originally Posted by Cerberus66
(Post 4851048)
Those appear to be lease return engines. My bet is they have next to no hours, crass hatch is crystal clear. If they have flat top pistons they are 10:1, the Rods were built by SCAT they are prostock I beams. the rod caps are cracked or they could be machined, they transitioned to cracked ones. They are bronze bushed with small ends tapered.
Fuel injectors are Bosch 89lb high imp injectors. very valuable and are sourced from the BMW M series platform. The oil pan has two different baffles, they do fit any mercruiser installation. The R block will also accept JP double row timing set with multi key. The crankshaft is very likely a Kellog crankshaft. Kellog and Dr Gu no longer manufacture cranks for PSI but PSI purchased thousands of them from Kellog. Every single crankshaft i have seen in even the 2021 builds have kellog cranks. You sound like you know a thing or two about these engines. I'll shoot you an email. [email protected] |
6 Attachment(s)
Originally Posted by Keith Atlanta
(Post 4851052)
They look a lot bigger maybe Cerberus66 will chime in.
The stock aperture may have only been 90, might have even been 85 I could probably stuff 4 fullsize cans inside this plenum. Not exaggerating. It's like a compact, upside-down tunnel ram. |
Originally Posted by Keith Atlanta
(Post 4851049)
Are those intake plenums bigger than the stock 8.1/496? They look a little bigger... The throat is 4 bolt rather than 3 as well, the TB hole looks bigger as well.
The intake is set up for LS TB, you can put on 103mm and even a 107mm TB The intake tracks are 14 inches long The intake was designed by Arizona Speed and Marine Jim Shofner. The intake was designed so you can remove the bottom and tune the runners. |
Originally Posted by Dragracer_Art
(Post 4851050)
Awesome.
I just popped the valve covers off and one engine had a bunch off loose rockers on one side... so I tightened them down and did a little more digging. Now I can see there is also no head gasket on that side and two lower head bolts are missing. lol Both engines rotate fine, so nothing broken, but the one missing a head gasket does feel like it binds every time that side has a piston at TDC... so zero deck clearence and carbon build-up is probably causing that or the valves are kissing pistons. Im at work until 4pm and have limited time to fool with them... so heads may have to come off tomorrow. Both engines do in fact have the LS style heads with trunnion mounted rockers... (see pics) I *may* just do a fresh rebuild on one of them and toss a Raylar cam in it to see what happens. Might need to flycut pistons... but otherwise feel like I got a solid deal here. I'm really curious how well these newer LS heads will work. As for cam and springs, The springs on these motors measure 45lbs seat pressure and 95lbs open. They suck because they are designed for VERY small camshaft. You will see when you pull the cam, its very small. The heads need bronze valve guides, They accept Pontiac type valves. Your head guy should be able to ID the proper ones. Keep the stems small as per the design. The rocker arms are LS7 Exhaust rocker arms, PSI uses them on both intake and Exhaust. We are rebuilding the trunnions with CHE trunnion upgrades. As for Raylar Cams on this head and engine combo......DO NOT TRY IT. you will be very disappointed. A custom ground cam is MUCH better. The head flow and velocity totally change the cam dynamics required to make power. The closest thing i can say is to use cam specs or design like a lsxr454 etc. We are working on these heads now. We are trying different valves sizes and designs. Remember these heads are true 15 degree BBC heads. A very radical difference from what most shops know. The flow and velocity of these heads changes everything BBC research has ever done. We have produced 600hp x 600lbft motor on a very mild cam using stock items. Those heads will flow about 420-430cfm. We will be publishing our results and offering CNC porting on them. We are going to a 900-1.00 lift cam with a LSA of 116 on our premier motor and shooting for 900-1000 hp NA. |
Do these accept standard exhaust ? If no, does someone make them for marine and how much ?
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12 Attachment(s)
Originally Posted by Cerberus66
(Post 4851057)
As for cam and springs, The springs on these motors measure 45lbs seat pressure and 95lbs open. They suck because they are designed for VERY small camshaft. You will see when you pull the cam, its very small.
The heads need bronze valve guides, They accept Pontiac type valves. Your head guy should be able to ID the proper ones. Keep the stems small as per the design. The rocker arms are LS7 Exhaust rocker arms, PSI uses them on both intake and Exhaust. We are rebuilding the trunnions with CHE trunnion upgrades. As for Raylar Cams on this head and engine combo......DO NOT TRY IT. you will be very disappointed. A custom ground cam is MUCH better. The head flow and velocity totally change the cam dynamics required to make power. The closest thing i can say is to use cam specs or design like a lsxr454 etc. We are working on these heads now. We are trying different valves sizes and designs. Remember these heads are true 15 degree BBC heads. A very radical difference from what most shops know. The flow and velocity of these heads changes everything BBC research has ever done. We have produced 600hp x 600lbft motor on a very mild cam using stock items. Those heads will flow about 420-430cfm. We will be publishing our results and offering CNC porting on them. We are going to a 900-1.00 lift cam with a LSA of 116 on our premier motor and shooting for 900-1000 hp NA. I will absolutely be using these heads. I couldn't resist... and had to pop off the intake and cylinder head that was missing the head gasket. Not seeing any smoking gun or broken stuff... but there is alot of carbon and oil in the chambers. Im guessing the guides or seals are shot. Cam and lifters still look new. Cylinder walls (as you mentioned earlier) still have cross hatch and zero ridge at the top of the cylinders. They will clean up real nicely with a quick hone. And yeah... the beehive springs are terribly soft. I can easily push them open with the palm of my hand. |
Originally Posted by Dragracer_Art
(Post 4851060)
Yeah I have to agree. Ive had Dart Big Chief heads on motors in the past... and these OEM iron heads look really neat. Ports look PLENTY big and chambers are shallow with flat valve angles.
I will absolutely be using these heads. I couldn't resist... and had to pop off the intake and cylinder head that was missing the head gasket. Not seeing any smoking gun or broken stuff... but there is alot of carbon and oil in the chambers. Im guessing the guides or seals are shot. Cam and lifters still look new. Cylinder walls (as you mentioned earlier) still have cross hatch and zero ridge at the top of the cylinders. They will clean up real nicely with a quick hone. And yeah... the beehive springs are terribly soft. I can easily push them open with the palm of my hand. https://cimg3.ibsrv.net/gimg/www.off...78ade57fa.jpeg your oil pans will look like this. |
Originally Posted by Dragracer_Art
(Post 4851060)
Yeah I have to agree. Ive had Dart Big Chief heads on motors in the past... and these OEM iron heads look really neat. Ports look PLENTY big and chambers are shallow with flat valve angles.
I will absolutely be using these heads. I couldn't resist... and had to pop off the intake and cylinder head that was missing the head gasket. Not seeing any smoking gun or broken stuff... but there is alot of carbon and oil in the chambers. Im guessing the guides or seals are shot. Cam and lifters still look new. Cylinder walls (as you mentioned earlier) still have cross hatch and zero ridge at the top of the cylinders. They will clean up real nicely with a quick hone. And yeah... the beehive springs are terribly soft. I can easily push them open with the palm of my hand. those are 9:1 pistons (Dished) you have to remember though. The head combustion chambers are much smaller than any 8.1 vortec head. A difference of 114cc to 78-83cc maybe even 87cc I forget exactly. But it is a big difference. |
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